The most common cause of shoulder pain is rotator cuff tendinitis. The term “tendinitis” is wrong. The word, “tendinitis” implies there is inflammation. In almost all cases of what is called rotator cuff tendinitis, there is very little inflammation. What is seen is wear and tear.
Rotator cuff problems should be referred to as rotator cuff tendinopathy. This is also called impingement syndrome. This condition may occur suddenly or may be chronic. The major finding is pain in the shoulder with lifting the arm out to the side and with lowering the arm as well. In some cases of acute tendinopathy, pain may come on suddenly. This presentation often occurs in younger patients.
Deposits of calcium may be seen in those patients who have an acute presentation with severe pain.
Inflammation of the bursa, what is termed the subacromial bursa, may also be seen.
Pain due to this conmdition is felt on the outside of the shoulder and is aggravated by different types of movement. Activities of daily living are affected. For instance, there may be difficulty with dressing and undressing. In addition, there is often pain at night.
On examination loss of range of motion is present. Another sign is that pressure placed on the rotator cuff by the physician will cause pain.
There are many different causes of rotator cuff tendinopathy. Overuse is probably the most common cause, particularly in older adults. Overhead activity is often seen as a primary cause.
The reason this kind of shoulder problem develops is that there is pressure on the rotator cuff tendons caused by squeezing of the tendons between the head of the humurus and the acromion of the shoulder blade. Also, as patients get older, the blood supply to the rotator cuff decreases. This leads to both wear and tear on the tendons, as well as loss of strength in the muscles.
In addition, spurs from osteoarthritis develop on the under surface of the joint that joins the clavicle to the acromion (acromioclavicular joint). This causes more wear and tear on the tendons.
The treatment begins with the proper diagnosis. The diagnosis is made usually on clinical grounds. It may be confirmed by magnetic resonance imaging. Diagnostic ultrasound is also a good diagnostic test.
Once the diagnosis is established, treatment consists of rest, moist heat, and physical therapy. The physical therapists will prescribe ultrasound and range of motion exercises. Non-steroidal anti-inflammatory drugs may also be useful.
The most frequent treatment applied is an injection of glucocorticoid into the subacromial bursa. This should be administered using ultrasound needle guidance.
In addition, following the steroid injection, the patient should keep their arm in a sling for approximately 3 days.
Most patients will respond to this treatment regimen.